喷雾干燥法制备牛蒡精粉工艺研究

鲜牛蒡经清洗、切片、热烫、护色、打浆、胶磨后进行喷雾干燥,制备富含多糖和蛋白质等营养成分的牛蒡精粉,研究影响喷雾干燥效果的各种因素,以得到最佳工艺参数.结果表明：牛蒡切片热烫后采用1%柠檬酸＋0.4%抗坏血酸＋0.5%氯化钙护色液浸泡30 min,料水比1∶3,进风温度200℃,雾化器频率为60 Hz.在此条件下,牛蒡精粉为白色粉末,得率7.25%,固形物回收率55.77%,溶解率超过85%,含水量4.13%,多糖含量16.50%,精粉蛋白含量16.63%,灰分含量5.17%,粗纤维含量0.14%.采用喷雾干燥法制备牛蒡精粉,是对鲜牛蒡进行深加工的有效途径.     

负载型复合氧化物催化剂WO_3/(TiO_2-SiO_2)催化性能的研究

用气相流动吸附法制备复合载体,用浸渍法制备WO3/(TiO2-S iO2)催化剂。应用LRS和TPR技术研究WO3在复合载体TIO2-S iO2表面的分散状态,发现TiO2在S iO2表面的分散可增强WO3与载体之间的相互作用,提高WO3在载体表面的分散阈值。另外TPR实验证明,TiO2的存在大大改善WO3的分散状态,虽然使WO3在TiO2-S iO2的还原温度升高,但在TiO2的调变下,WO3与载体之间的作用增强。负载于经TiO2调变的S iO2上的催化剂其HDS、HYD、BHD活性高于负载于单纯S iO2上的催化剂的活性。     

洋葱醋蛋复合粉喷雾干燥工艺研究

目的:优化新型洋葱醋蛋复合粉喷雾干燥工艺。方法:选择进风温度、喷雾流量、溶液固形物含量与助干剂比值共3个因素,以喷雾干燥后洋葱醋蛋粉润湿性、产品得率和溶解度为响应值,分别采用正交试验设计法及综合平衡法优化,以得到洋葱醋蛋粉喷雾干燥最佳工艺条件。结果:洋葱醋蛋粉喷雾干燥的最佳工艺条件为:进风温度为145℃,喷雾流量为15 mL/min,总固形物含量与助干剂的比值为4∶6。结论:在此优化的工艺条件下制得的产品冲调特性最佳,对洋葱醋蛋粉的生产具有一定的理论指导意义。     

WO3在气相吸附法制备的TiO2/SiO2复合载体表面的分散状态

采用气相流动吸附法制备了TiO2／SiO2复合载体，用浸渍法制备了WO3／(TiO2／SiO2)催化剂，应用，XRD和LRS等技术研究了TiO2在SiO2表面及WO3在TiO2／SiO2复合载体表面上的分散状态．结果表明，TiO2在复合载体中的载量低于其分散阈值时，它在SiO2表面呈单层但非密置单层分散；WO3在催化剂中的载量低于其分散阈值时，它在复合载体表面亦呈单层但非密置单层分散．TiO2在SiO2表面上的分散可改善WO3的分散状态，提高WO3在SiO2表面上的分散阈值．     

WO_3微/纳米结构的合成及气敏性能表征

以钨酸钠为钨源,用草酸做辅助剂,在90℃水浴中通过简单的液相沉淀法一步合成了由纳米片组装的近球形结构的WO3.通过XRD、SEM对WO3微纳米结构、尺寸形貌等进行了表征,并利用WS-30A气敏测试系统对产物的气敏性能进行了表征.结果表明:所制备出的近球形WO3微纳米结构粉体具有良好的结晶度,并且对冰乙酸、乙醇、甲苯及甲醛表现出一定的灵敏度,其中对冰乙酸的灵敏度最高.     

表面活性剂对复合电沉积法制备纳米碳管复合镀层的影响

采用复合电沉积法制备纳米碳管复合镀层,在控制实验基本工艺参数不变的条件下,通过加入不同的表面活性剂进行电镀,测量纳米碳管的质量占所得镀层总质量的百分比。经过分析后可以得到:阳离子表面活性剂更有利于制备纳米碳管复合镀层的电沉积;而阴离子表面活性剂以及非离子表面活性剂则不利于制备纳米碳管复合镀层的电沉积。     

猪胫骨-鸡骨架复合骨汤粉喷雾干燥条件研究

研究了喷雾干燥条件对猪胫骨-鸡骨架复合骨汤粉品质等特性的影响,经过单因素试验及响应面优化实验,得出了回归模型且模型显著（P<0.05）,确定了复合骨汤乳液最佳喷雾干燥条件：物料浓度为20%(w/w),进风温度为170℃,进料速度为5 mL/min,此条件下经喷雾干燥所得的复合骨汤粉的色泽均匀,骨汤风味浓郁,产品得率和品质均较高,感官评分与预测值接近,说明运用响应面法优化得到的干燥条件准确可靠。     

发芽糙米苦瓜复合营养粉的研制

目的:以发芽糙米粉、苦瓜为主要原料,研制发芽糙米苦瓜复合营养粉。方法:在单因素试验基础上,运用正交试验确定最优苦瓜粉的喷雾干燥条件以及复合营养粉原辅料的最佳配比。结果:发芽糙米的较优烘烤温度为140℃条件下烘烤40min,发芽糙米粉碎最佳粒径为80~100目;苦瓜粉的最佳喷雾干燥工艺为进风温度140℃,进料频率控制在17r/min,物料温度为45℃;制备发芽糙米苦瓜复合营养粉最佳配比为固定发芽糙米粉与苦瓜粉比5∶2,以发芽糙米苦瓜混合粉按100%计,辅料水溶性大豆多糖(Soluble soybean polysaccharides,SSPS)的添加量为5%,木糖醇为20%,麦芽糊精为12%。结论:通过此工艺制得的产品口感细腻,甜度适中,GABA含量为23.32mg/100g,具有一定的市场开发前景。     

Gd和TiO_2共掺杂的WO_3纳米粉体的制备及其光催化性能

以Na2WO4和C16H33(CH3)3NBr为原料,通过液相沉淀法制备了WO3纳米粉体,用钛酸胶体溶液浸滞法制备了TiO2掺杂的WO3纳米粉体,再用Gd(NO3)3溶液浸滞TiO2掺杂的WO3纳米粉体法制备了稀土Gd和TiO2共掺杂的WO3纳米粉体,并采用透射电子显微镜、紫外-可见漫反射吸收光谱和X-射线衍射对其结构进行了表征.实验结果表明,稀土Gd和TiO2共掺杂拓展了WO3的光响应范围,提高了对可溶性染料罗丹明B(RB)的吸附作用,使WO3对RB的光催化降解活性和光稳定性得到了显著提高.     

纳米铁氧体复合涂料的制备及性能研究

运用原位乳液聚合法和机械共混法两种方法制备了纳米Fe3O4和BaFe12O19改性丙烯酸树脂涂料,并对复合涂料的性能进行了研究,发现原位乳液聚合法制备的纳米Fe3O4和BaFe12O19改性丙烯酸树脂涂料的吸波性能明显优于机械共混法制备的纳米复合涂料．     

Experimental study on spray cooling performance of pressure atomizing nozzle

Aiming at the problem of air-cooled condenser output limit,a spray humidification system was presented to reduce the inlet air temperature.The pressure atomizing nozzle TF8 was chosen for inlet air spr...     

Resuspension of wall deposits in spray dryers

Wall deposition occurs in spray dryers when dried or partially dried particles contact and adhere to the walls during operation, thus reducing the yield of product collected. Wall deposits also present a product contamination risk and a fire or explosion risk when spray drying products that oxidize exothermically, such as milk powder. Re-entrainment is the resuspension of spray dryer wall deposits into the main gas stream for collection as product. Literature suggests that the process for re-entrainment of particles from spray dryer wall deposits is strongly dependent on particle size and gas velocity.     

Review:Resuspension of wall deposits in spray dryers

Wall deposition occurs in spray dryers when dried or partially dried particles contact and adhere to the walls during operation, thus reducing the yield of product collected. Wall deposits also present a product contamination risk and a fire or explosion risk when spray drying products that oxidize exothermically, such as milk powder. Re-entrainment is the resuspension of spray dryer wall deposits into the main gas stream for collection as product. Literature suggests that the process for re-entrainment of particles from spray dryer wall deposits is strongly dependent on particle size and gas velocity.     

改性MCM-41分子筛负载钼钴系催化剂的TPS研究

本文采用程序升温硫化(TPS)技术研究了负载于MCM-41分子筛的钼钴系催化剂的性能。根据TPS结果可知:(1)载体和MoO_3相互作用强弱顺序如下:Al_2O_3>Al_2O_3-MCM-41>MCM-41>TiO_2-MCM-41,由此推断TiO_2具有削弱MCM-41和MoO_3作用的能力,而Al_2O_3则相反,它增强了MoO_3和MCM-41的相互作用;(2)助剂CoO对负载在未经改性的MCM-41载体上的MoO_3的硫化没有明显的促进作用,这和以Al_2O_3为载体的情况不同,TPS结果表明在Al_2O_3上MoO_3和CoO可能生成Co-Mo-O复合相从而促进了MoO_3的硫化;(3)助剂CoO对负载在经TiO_2和Al_2O_3改性的MCM-41上的MoO_3的硫化起促进作用。     

氯化胆碱的微胶囊化

应用微胶囊技术进行了包埋氯化胆碱的研究。用多种水溶性物质做壁材 ,用喷雾干燥法进行包埋 ;通过测定包埋率 ,对壁材和芯材的配方数据进行筛选 ,得出了最佳壁材、芯材配方 ;同时 ,作了机理分析     

Wear performance of metal parts fabricated by selective laser melting: a literature review

Selective laser melting (SLM) is one type of additive manufacturing which produces metal parts by powder bed fusion. Since the materials undergo repeated and sharp heating/cooling cycles, the SLMed parts have unique microstructures. The relations among SLM processing parameters, resultant microstructures, and mechanical properties have been investigated by many researchers. However, the wear performance of SLMed materials under various contact conditions has not been carried out until recently. This paper is a presentation of previous and recent research related to wear performance. This is a crucial aspect if SLM is to be expanded to produce friction pairs. Wear rates and mechanisms of the SLMed materials under dry, boundary lubrication, cavitation erosion, and corrosion conditions are discussed and compared with conventionally processed (CP) materials. SLMed materials benefit from fine grains and high hardness, which have higher wear resistance than CP materials. Moreover, a unique tribo-layer on the surface of the SLMed part is found to protect the bulk material under boundary lubrication conditions. An optimized combination of processing parameters increases part density, which further improves the wear resistance. Future work includes studying the influence of pores on the deforming and lubricating behaviors from dry conditions to different lubrication regimes. The final target is to actively control the processing parameters to obtain desirable material properties for improving wear performance.     

太阳能多晶硅铸锭用熔融石英坩埚氮化硅涂层的制备

熔融石英坩埚是生产太阳能多晶硅铸锭的必要容器,为脱模方便,需在其内表面喷涂一层氮化硅．采用高纯氮化硅粉在国产石英坩埚上喷涂,研究喷涂氮化硅浆液时石英基底温度和涂膜厚度对石英坩埚氮化硅涂层结合强度的影响．结果表明：采用高纯氮化硅粉喷涂石英坩埚基底,温度应在40℃以下且喷涂涂层厚度不宜超过80μm．     

螺旋藻中部分常量和微量元素的FAAS法测定

干法灰化,消化液(HNO3∶HClO4=4∶1)溶解藻粉,用火焰原子吸收法直接测定其中的Ca、Mg、Zn、Mn、Cu等,结果显示,螺旋藻粉有丰富的各元素含量,该方法具有方法简便,快速可靠等优点,具有良好的精密度和准确度,平均回收率在99.07%～103.98%之间,在实际应用方面获得了令人满意的结果.     

基于PLC和IC卡的干混奶粉配送控制系统

以奶粉干法生产过程为例,提出了采用IC卡和PLC的粉仓车配送控制系统方案。主PLC通过PROFIBUS网络通讯与各子PLC通讯,IC卡读卡器与子PLC的自由口连接,利用STEP7编程软件对PLC与读卡器进行程序设计,实现粉仓车上的IC卡识别与纠错控制,并利用上位机对其进行远程监控,减小奶粉干混配送过程出错的可能性,提高食品加工过程的安全性。结果表明,该系统可提高生产效率,降低工人的劳动强度,为奶粉等食品类工业生产的厂内干粉配送控制系统的进一步研究提供了实践基础。